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Contingencies (Details) | 6 Months Ended
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Jun. 30, 2016 USD ($) site
Commitments and Contingencies Disclosure [Abstract] |
Number of Superfund sites for which company may be liable | site | 1
Workers' compensation deductible (per occurrence) | $ 1,000,000
Workers' compensation accrued liability | 18,800,000
Outstanding letters of credit | 17,800,000
Estimate of possible loss | $ 0

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